This section provides background information related to the present disclosure which is not necessarily prior art.
In providing flow of a liquid, such as water, that is highly supersaturated with a gas such as oxygen, within a host liquid, it has been found that the level of liquid flow rates that ensure laminar flow through small bore tubes is critical for providing bubble-free delivery of the liquid. For example, water that is supersaturated with oxygen at 1 ml O2/g water (at standard temperature and pressure, upon release of the dissolved gas) can be delivered through a silica tubing 100 microns or less in diameter within host liquids without bubble formation, for liquid flow rates of about 1 ml per minute. This flow rate allows for a flow that is laminar, and does not include any cavitation or nucleation sites for formation of bubbles. Such a system is disclosed in U.S. Pat. No. 5,569,180 to Spears. Such a system allows for the injection of the oxygen supersaturated liquid without the generation of bubbles into a system that is sensitive to the introduction of bubbles or other non-fully dissolved gases. Such sensitive systems include the human body in particular the vasculature system within the human body.
Such a system that introduces a substantially bubble-free liquid into a host liquid, such as an intravascular space, does not permit generation of bubbles during rapid dilution (for example, less than about 2-3 bars equilibrium oxygen partial pressure upon mixing) in the host liquid. The tubes for such systems are designed to eliminate heterogeneous nucleation sites along the inner surface of the tubes and at the proximal and distal ends of the tubes.